Superheater-boiler.



A. :0. PRATT SUPERHEATER BOILER. AIPLIOATION FILED JUNE 18, 1912.

Patented Dec. 17,1912} I mam.-

' ouses.

a York, have invented certain new and usemore banks of tubes either straight through cally inclined direction.

cat-ion of my invention I have shown it in -,struction, the drawing being a vertical lonwater-drums connected by banks of tubes 3 shown. The bank 3 comprises a row of dially.

' which the tubes 3 are located, across the top drum 2.

"UNITED STATES PATENT oFEIoE.

ARTHUR D. PRATT, or NEW YORK, N. Y.

, ASSIGNOR To THE nancoox & wILcox comramr, or BAYONNE, NEW JERSEY, A CORPORATION or NEW JERSEY.

SUPERHEATER-BOILER.

Specification 01 Letters Patent.

Patented Dec. 1'7, 1912.

Application filed .Tune 18, 1912. Serial No. 704,278.

To all whom may concern Be it known that I, ARTHUR D. PRATT, a citizen of the United States, residing at New York city, borough of Manhattan, in the county of New York and State of" New ful Improvements in Superheater Boilers, of which the following is a specification.

My invention relates to superheater boilers, and more particularly to that form of water tube boiler-in which there are two or out their length or withcurved or bent ends, and which extend vertically or in a verti- For the purpose of illustrating one appliconnection with a boiler of standard congitudinal section through the upper part of the boiler.

Referring to the drawing, the numerals 1 and 2 designate upper transverse steam and and 4 with transverse mud drums, not

tubes 5, and the bank 4 a row of tubes 6, the tubes of bothof said rows being curved orbent at their'en'ds to enterthe drums ra- Sup orted between the tubes 5 and 6 is a baflle The gases from the furnace are directed through the uptake pass in of baflle 7 and then through the downtake pass, in which the tubes 4 are located, to the stack outlet. Baiile shelves 8 and 9' direct the gases along and across the water tubes. The drums 1 and 2 may be connected by the usual pipes 10 and 11. 1

Between the banks of tubes I place a superheater comprising two sets of U-shaped tubes 12 and 13 with their legs extending upwardly above the top of'the bafile 7, the tubes 12 being in the uptake pass and the tubes 13 in the downtake pass. The tubes 12 are expanded into cross boxes 14 and 15, and the tubes 13 into cross boxes 16 and 17. These boxes preferably extend through the side walls, and the box 16 is connected by pipe 18 with the steam space of the rear The boxes 17 and 14 are connect ed by a pipe 19 so that the steam from drum 2 enters box 16, and passes upwardly through the right hand legs and down the i left hand legs oftubes 13 to box 17, through i the connecting pipe 19 to box 14:, upwardly through the righthand legs and downwardly through the left hand legs of tubes 12 to box 1-5, and thence out through connection 20. It will be seen from this that the steam is first passed through the section of the superheater where the gases are relatively cool, and then into a section where the :temperature is relatively high. Although in both sect-ions of the superheater the steam travels both in the same direction and in a direction opposite to that of the other of the gases, the general flow of the steam is from the coolest to the hottest part. of the boiler. That is, boxes 16 and 17 are in the coolest part of the'boiler, and the boxes 14 and in the hottest part, the steam leaving by a connection from-the latter box- It will also be observed that the steam flows from box 16 in a direction opposite to the direction of flow of the gases through the downtake pass, and flows to the outlet, box 1-5 in a direction opposite to that of the di rection of flow of'the gases in the uptake pass. That is, the steam flows through the incoming legs of tubes 13, and the outgoing legs of tubes 12, counter to the direction of flow of the gases.

By. the method above described,'it will be seen that the principle of counterflow of steam and gases which is used successfully in separately fired superheaters is carried site sides of said baflie. one in the uptake pass and the other in the downtake pass.

2. A superheater boiler having two banks of tubes, a bafile between the banks. and a superheater comprising two connected sets of U-shaped tubes with their legs directed upwardly, saidsets being on opposite sides of said bafiie. one in the uptake pass and the other in thedowntake pass.

Y 3. A superheater boiler having two banks of tubes, a baflie between the banks forming uptake and downtake passes for the gases, a superheater comprising two connected sets of U-shaped tubes, one set being in the uptake pass and the other in the downtake pass, and inlet and outlet connections for the superheater whereby the inlet and outlet flow of the steam is in a direction opposite the direction of flow of the gases.

4. A superheater boiler having two banks of tubes, a battle between the-banks forming uptake and downtake passes for the gases,

U-shaped superheater tubes located in both 1-; passes, boxes into Which the legs of the su-' perheater tubes are expanded, a steam inlet 1 connection to one of the boxes in the downtake pass, a steam outlet from one of the of U-shaped tubes, one setbeing in the up- 4 take pass and the other in the downtake pass, said superheater sect-ions being so arranged that the steam enters the section 1n the-downtake pass in the direction opposite to the flow of the gases in the downtake pass, and leaves the section in the uptake pass in a direction opposite to the flow of gases in the uptake pass.

6. A superheater boiler having two banks of tubes, each bank including an inner row of tubes having their ends bent and separatedfrom the main body of the bank, a

bafiie between the said rows of bent tubes forming uptake and downtakc passes for the gases, a superheater comprising two connected sets of U-shaped tubes one set being in the uptake pass in the space between the main body of the bank of tubes and its inner row of tubes, and the other section being in the do-wntake pass in the space between the inain body of tubes and its inner row of bent tubes, boxes into which said superheater tubes are expanded, and a steam inlet to one of the boxes in the downtake pass and a steam outlet connection from one of the boxes in the uptake pass.

In testimony whereof I have hereunto signed my name in the presence of two subscribing Witnesses.

ARTHUR D. PRATT.

Witnesses:

E. P. TERRY, JOHN A. W. DIXON. 

